The supply of conventional crude oils is steadily diminishing. Heavy crudes are in greater supply but they contain higher boiling components and high sulfur contents which make them of lower value. The catalytic processing of these heavy crudes would maximize the yields of low-sulfur lower-boiling, high-value products. However, these heavy oils contain high contents of contaminant metals, such as nickel, vanadium, and iron, and coke-forming carbon materials that make catalytic processing very costly due to increased gas. increased coke and decreased gasoline production.